The measurement of Physical Workload and Mental Workload Level of Medical Personnel

In ergonomics, the workload must be appropriate physical abilities, cognitive abilities, as well as limitations [1]. The workload is divided into two categories. The first is the physical workload. It occurs if there difference workload toward the physically workers' ability. The second is the mental workload. It is the difference between mental workload and psychic abilities workers. The workload related to worker fatigue. Several activities effect fatigue included working too hard, the wrong of posture, and inappropriate conditions. The workload is influenced by factors external and internal. Physiologically, mental activity is a type of work with low caloric. However, mental activity is substantial than physical activity as it involves the brain [1]. The mental activity involved information received action, perception, interpretation, to a decision-making activity [2]. Medical personnel is responsible for patients. However, their activity also allows for stress. Stress on medical personnel influence work performance. Adverse physical and mental conditions affect their work. It influences the quality of services to patients. According to Colligan, et al. [3], commonly, error rates of medical personnel are in the ARTICLE INFO ABSTRACT

As the primary health reference center, a hospital must provide excellent quality services to each patient. The impact of the extreme physical and mental workload causes negligence in activities. It affects the quality of services provided by medical personnel. This study investigated the level of mental workload and physical workload in medical staff in a hospital. This study was conducted at 15 units in the hospital. The mental workload was assessed using the NASA-TLX Questionnaire. The physical workload analysis was carried out with the Heart Rate reserve percentage of medical personnel. This study shows that the mental workload of nurses in the Intensive Care Unit (ICU) is higher than the other units. Whereas the calculation of physical load using % HR reserve turns out the nurse's head in-unit class 1 has the highest value than the other unit. The statistical analysis showed a difference in the general practitioner workload toward the Head of Nursing. intensive care unit (ICU), Radiation Oncology (RO), and emergency department (ED). Physiological and psychological factors make medical errors occur. Some causes included increased workload, fatigue, ineffective communication, and wrong information [4,5]. The nurse is a work that requires productive activity and minor error [3,6]. Changing of nurse mental workload affected patient health and safety [7,8]. Some studies on mental workload in the health sector have been carried out, such as [Mazur,et al. [9], 10, 11], [Walters and Webb [12], 13, 14], and Liang, et al. [15]. However, in previous studies, the assessment of mental workload was carried out in one work unit. To our knowledge, there is no study to assess the mental workload for the complete hospital unit.
Ergonomics aims to increase the efficiency, health, safety, and comfort of humans in the workplace [16][17][18]. In ergonomics, the researcher can measure physical workload and mental workload. The relationship between mental workload and physical workload attracts the attention researcher. In some activities, physical and mental tasks increase the workload [19][20][21]. Mental workload is a factor that affects of performance of an activity. Some of these mental tasks required concentration, attention, memory, planning, and decision making [22]. Therefore, mental workload influences fatigue, and it increases operating errors [23]. It correlates with workplace factors and physical workload as one of the hazards [24,25].
The mental workload and effects on the performance of physical workload toward worker must measure [22]. Therefore, this research aims to measure the mental workload and the physical workload of medical personnel. Physical workload evaluation is conducted with a percentage of % Heart Rate Reserve (HR Reserve) medical personnel [26][27][28][29]. It is done to determine the beats per minute based on the maximum pulse, work pulse, and resting pulse. The measurement of mental workload used the NASA-TLX method [30]. National Aeronautics and Space Administration Task Load Index (NASA-TLX) is a tool to assess individuals' workload. The NASA-TLX has a six-item. Initially, It used to measure workload in the laboratory, aviation. Furthermore, it has been applied to workload measurement in several sectors such as nuclear energy, transportation, and health care [30][31][32][33][34][35].

Methods
In this research, workload measurement is divided into 2. The first is the physical workload, and the second is the mental workload. The technique used is described as follows:

Measure physical Workload
The medical personnel's physical workload was measured using pulse rate. Heart rate is used to measure physical activity levels. Commonly, it is an average of beats per minute [28]. We measured the pulse of the worker before work. Furthermore, they take a rest for 30 minutes. The Karvonen Formula was used to measure the intensity of activity [36] (see Equation (1) and (2)). The Heart Rate Reserve (HR Reverse) expressed in percentage is formulated in Equation (3). Furthermore, there are five classifications in % HR Reverse. Less than 30% indicate no fatigue. 30% -60% describe the need for improvement. 60%-80% describe work in no time. 80%-100% describe urgent action is required. And, more than 100 describe no activity allowed.

Mental Measure Workload by NASA-TLX Methods
NASA-TLX instruments were given to respondents after they complete activities. The researcher explains NASA-TLX Instruments to respondents. It is carried out to ensure appropriate answer respondents. The workload is measured using procedures developed by Hart and Staveland [30]. Table 1 describes the NASA-TLX Rating Scale and Definitions. NASA-TLX procedure is explained as follows: 1). Weighting: NASA-TLX questionnaire given to respondents contained paired questions. In the NASA TLX method, there are six indicators as Mental Demand (MD), Physical Demand (PD), Temporal Demand (TD), Performance (P), Effort (EF), and Frustration (F). The questionnaire has a low to a high rating (0-5). In this section, respondents choose the dominant indicator that causes workload. 2). Provision Rating: In this section, the respondents are asked to rate the six mental workload indicators. The rating is given depending on the mental workload of the respondent. The score is between 0 to 100. In the mental load score, the weights and ratings for each multiplied indicator are then summed and divided by 15 (the number of pairwise comparisons). 3). Calculating the product's value: this value is obtained by multiplying the rating by the factor weight for each indicator. 4). Calculated Weight Workload (WWL): Sum all weighted workload of product. 5). Calculated WWL Score: Calculate the average weighted workload. 6). Score Interpretation :The score interpretation based on calculated WWL are low (0-9); medium (10-29); Rather high (30-49); High (50-79); very high (80-100).

Data collecting
Respondents in this study were medical personnel with criteria 1.) Experienced working for more than one year. Therefore, they were personnel who know the level of difficulty of the work. 2). The medical staff was in the right, physically, and spiritually condition. The study was conducted on 15 units of medical personnel. Physical Workload and Mental Workload were assessed from July 2017 through August 2018 in Malang Indonesia hospital. The total number of respondents in this study was 15. Respondents in this research were five general practitioners, Head of Emergency Room Nursing, Head of Child Nursing, Head of Special Service Unit for Stroke Nursing, Head of ICU Nursing, Head of Class 1 Nursing, Head of Class 2 Nursing, Head of Class 3 Nursing, Head of VIP Class Nursing, Head of Childbirth Nursing and Head of Surgery Nursing.

Data analysis
We compared the Mental workload of the General Practitioner toward the Head of the Nurse. It was carried out using the independent sample t-test [37,38]. We used Minitab version 14 to solve the independent sample t-test. We have hypotheses that there are mental workload differences between a general practitioner and head of nursing. Table 2 shows the Pulse Rate of Medical Personnel. Furthermore, Pulse Rate is used to measure energy consumption. The result of energy expenditure and the energy consumption is shown in Table 3. Overall, Energy Expenditure respondents ware category lightly. Although category light, activity in medical give concentration [22]. Therefore, Heart Rate Reserve show some respondent in Need improvement category (Table 4). They are General practitioner 1, Head of ICU Nursing, Head of Class 1 Nursing, Head of Class 2 Nursing, and Head of Surgery Nursing. Moreover, respondents were category no fatigue.

Mental workload measurement
Some data was collected to measure mental workload. These data included the Paired Comparison and the rating score. Table 5 shows the Paired Comparison of General Practitioner. Table 6 describes the head of nursing paired comparison data. Table 7 shows a rating score of a general practitioner. Table 8 describes the rating score of the head of nursing. Moreover, data were used to measure WWL and average WWL. Table 9 shows the result of WWL and WWL average from General Practitioner. Table 10 describes the Result of WWL and WWL average from the head of nursing. Furthermore, the classification of medical personnel based on Nasa TLX Analysis is shown in Table 11. NASA-TLX measurement results showed that mental workloads were categorized as  [Mazur,et al. [9], 10, 11]. Therefore, medical work poses a significant mental workload.      Indicator  WWL  WWL  Average  MD  PD  TD  P  F  EF  respondent 1  450  180  80  320  0  270  1300  87  respondent 2  180  210  0  400  70  210  1070  71  respondent 3  200  50  50  350  70  210  930  62  respondent 4  200  100  50  350  0  210  910  61  respondent 5  140  140  210  210  140  210 1050 70   The result of compare means independent sample t-test is t count < t table (Table  12). Therefore, the initial hypothesis is accepted. The mental workload of general practitioners is different from the head of nursing. This study shows that the mental workload of nurses in the ICU is higher than the other units. However, the value of % HR reserve in the head of the nurse in class 1 has the highest amount compared to the unit other. The results of this study harmonized by Mazur, et al. [34]. Tubbs-Cooley, et al. [35] also found high correlations with the mental workload in ICU nurses. It is also proved that research Hoonakker, et al. [39] and Colligan, et al. [3]. Therefore NASA TLX is a helpful tool to measure mental workload [40]. NASA-TLX is helpful to measure the mental workload of medical personnel. Although the results obtained in previous studies vary, it is caused by various factors. Some factors included such as the practical design of work, resources available, a culture of teamwork and collaboration, and employee prosperity [7,41].

Conclusion
The measurement results of physical workload medical personnel are a mild category. However, for mental workload measurement, The General practitioner's mental workload is category high. Furthermore, heads of nursing were classified in a very high grade. In mental and physical workload, nurses produced the highest score. They always are alert and responsive in helping patients. Hence, the workload in ICU nurses highest. Some that activity is encouraging, attracting, controlling, and operating medical devices. In addition, The highest physical workload is in nurses class 1. In this class 1, the head of nursing must focus on helping patients, and they always fast in helping patients. Moreover, they are required to still work quickly to helped patients properly. For future work, we suggestions for the next researcher. Some future research included investigating the physical and mental workload in another field such as Pharmacy and front officer in hospital. Furthermore, the future researcher can use another method, the physical and mental workload.